give ipfs get symlink support

License: MIT
Signed-off-by: Jeromy <[email protected]>

thirdparty/tar/extractor.go

@@ -2,6 +2,7 @@ package tar
 
 import (
 	"archive/tar"
+	"fmt"
 	"io"
 	"os"
 	gopath "path"
@@ -39,15 +40,21 @@ func (te *Extractor) Extract(reader io.Reader) error {
 			break
 		}
 
-		if header.Typeflag == tar.TypeDir {
+		switch header.Typeflag {
+		case tar.TypeDir:
 			if err := te.extractDir(header, i); err != nil {
 				return err
 			}
-			continue
-		}
-
-		if err := te.extractFile(header, tarReader, i, rootExists, rootIsDir); err != nil {
-			return err
+		case tar.TypeReg:
+			if err := te.extractFile(header, tarReader, i, rootExists, rootIsDir); err != nil {
+				return err
+			}
+		case tar.TypeSymlink:
+			if err := te.extractSymlink(header); err != nil {
+				return err
+			}
+		default:
+			return fmt.Errorf("unrecognized tar header type: %d", header.Typeflag)
 		}
 	}
 	return nil
@@ -79,6 +86,10 @@ func (te *Extractor) extractDir(h *tar.Header, depth int) error {
 	return nil
 }
 
+func (te *Extractor) extractSymlink(h *tar.Header) error {
+	return os.Symlink(h.Linkname, te.outputPath(h.Name))
+}
+
 func (te *Extractor) extractFile(h *tar.Header, r *tar.Reader, depth int, rootExists bool, rootIsDir bool) error {
 	path := te.outputPath(h.Name)
 

unixfs/archive/tar/writer.go

@@ -79,6 +79,8 @@ func (w *Writer) WriteNode(nd *mdag.Node, fpath string) error {
 		fallthrough
 	case upb.Data_File:
 		return w.writeFile(nd, pb, fpath)
+	case upb.Data_Symlink:
+		return writeSymlinkHeader(w.TarW, string(pb.GetData()), fpath)
 	default:
 		return ft.ErrUnrecognizedType
 	}
@@ -108,3 +110,12 @@ func writeFileHeader(w *tar.Writer, fpath string, size uint64) error {
 		// TODO: set mode, dates, etc. when added to unixFS
 	})
 }
+
+func writeSymlinkHeader(w *tar.Writer, target, fpath string) error {
+	return w.WriteHeader(&tar.Header{
+		Name:     fpath,
+		Linkname: target,
+		Mode:     0777,
+		Typeflag: tar.TypeSymlink,
+	})
+}